Dyes are widely used in a variety of technical fields. In the field of photoelectric conversion devices such as solar cells, for instance, dyes having photosensitizing properties have been used in dye-sensitized photoelectric conversion devices. Dye-sensitized photoelectric conversion devices are expected to theoretically achieve high efficiency and be produced at lower cost than those having a conventional silicone semiconductor.
A dye-sensitized photoelectric conversion device has an electrode having an oxide semiconductor using a dye carrier. In the dye-sensitized photoelectric conversion device, the dye is excited on absorbing light falling on the device and injects electrons into the carrier to perform photoelectric conversion.
Studies have been conducted on improvement on a carrier and the adsorbability of a dye (property of being adsorbed) onto a carrier as an approach to improve the conversion efficiency and durability of dye sensitized photoelectric conversion devices. That is, improvements on physical and chemical adsorbability of a dye would allow for efficient movement of the excited dye energy to the carrier and prevent the dye from desorving into the device, specifically into the electrolyte, and the like. Disclosed techniques for improving dye adsorbability include a dye molecule having a carboxyl group bonded thereto via an amide linkage (see patent document 1 below) and a dye molecule having two carboxyl groups (see patent document 2 below).
A solar cell, one of the main applications of the dye-sensitized photoelectric conversion device, is required to have high durability by the very nature of use. In this regard, a known dye and a photoelectric conversion device using the known dye have not yet achieved sufficient characteristics.